Door operator mechanism



Aug. 7, 1962 w. M. REYNOLDS DOOR OPERATOR MECHANISM 3 Sheets-Sheet 1'Filed March 4, 1960 INVENTOR. haze: M Pam/040.5

Aug. 7, 1962 w. M. REYNOLDS DOOR OPERATOR MECHANISM 5 Sheets-Sheet 2Filed March 4, 1960 rates Unite I misses Patented Aug. 7,. 1962 ()hioFiled Mar. 4, 196%, Ser. No. 12,818 2 Claims. (Cl. 268-59) Thisinvention relates to door operator mechanism and more particularlymechanism for moving an overhead garage door to open and closedpositions.

The invention also relates to an electric motor drive and controltherefor which automatically amd safely determines the sequence of thedoor movement.

Numerous operating mechanisms have been proposed for the control andactuation of overhead garage doors. Certain of the prior art deviceshave included electric motors and counter-balancing springs to assist inmoving the garage door to open and closed position. It has also beenproposed in the prior art door operators to mount an elongatedcylindrical shaft in a horizontal position above the door to rotate theshaft and to reciprocate a carriage along said shaft by means ofinclined rollers on the carriage in frictional engagement with theshaft.

The principal object of the present invention is positively to preventthe motor of such a door actuator remaining so energized as to urge thedoor to move farther in the same direction after it has reached thenormal limit of its motion. in that direction and thereby eliminate thepossibility of rapidly wearing out the actuator and burning out themotor, which has been one of the defects of prior door actuators.

A further object is to decrease wear and increase the life andreliability of doors and door operators by controlling the motor so thatthe power is cut off just before the door reaches the limit of itsmovement in either direction, and at the same time cutting off the motorpower Whenever the door encounters excessive resistance at any point inits travel.

A further object is to simplify and improve the operation andreliability of an automatic motor control for a door operator which maybe actuated by limit controls or by overload controls or both.

Other objects and advantages relating to reliability in operation,ruggedness of construction and safety in use will appear from thefollowing description and the appended drawings wherein:

FIG. 1 is an elevation showing the door operator mechanism madeaccording to my invention mounted in a garage and connected to thegar-age door;

FIG. 2 is a plan view of the operator mechanism shown in FIG. 1;

FIG. 3 is a perspective view looking from below at the actuatormechanism and illustrating the carrier and parts of the electric controlcircuit;

FIG. 4 is a transverse view with parts in section taken through thecarrier as indicated in plane 44 of FIG. 1;

FIG. 5 is an elevation showing the parts of the safety mechanismembodied in the door operator according to my invention; and

FIG. 6 is a diagrammatic showing of the electric circult and certainparts of the operator as related to the electrical circuit. I

Referring to the drawings, the door operator, indicated in its entiretyas at 5, is mounted horizontally within the garage adjacent the dooropening 6. The right-hand end of the operator mechanism, as viewed inFIGS. 1 and 2, includes a transverse bracket 7 which is supported in anysuitable Way, as by being secured above the garage door 8 to verticalstuds 9. The left-hand end of the operator may be suspended from thegarage roof (not shown) by and 39 to eachother;

means of depending angle irons 10 and 11 which are secured as at 12 and13 to a transverse bracket 14.

In the illustrated embodiment, horizontally disposed angle iron 15 iswelded at one end to the bracket 7 and at its other end to the bracket14. A parallel angle iron 16 is spaced from the first iron 15 and issimilarly welded to the brackets 7 and 14. Preferably the angle irons 15and 16 are arranged so as to face each other and provide opposite websat 45 to the horizontal as best shown in FIG. 4..

The angle irons 1'516 and the brackets 7-14 form a rectangular framewhich supports a tubular drive shaft 18. The shaft 13 is provided with astub shaft 19' atits right-hand end and a stub shaft 20 at its left-handend; The stub shafts 19 and 20 are preferably welded within the tube 13as indicated in the cut away section in FIG. 2. The stub shaft portions19 and 20 are journalled in bearings 21 and 22 carried by the brackets 7and 14, respectively. A spring 23 surrounds the stub shaft 19 and aspring 24- surrounds the stub shaft 20 so as to bias the tubular member19 to a central position with respect to the end brackets 7 and I4.

The outer end of the shaft 20 projecting beyond bracket 14 is providedwith a pulley 25 which receives a V -belt 26 that is driven by a pulleyon the driving motor 27. The rectangular frame supporting the tubulardrive shaft 13 may be suitably reinforced by cross members 28 and 29.The cross members 28 and 29 are each provided with down-turned ears suchas 3th and 31 so that the midportions of the cross members 28 and 29 arespaced above the tubular member 18 and also clear the rollers on thereciprocating carriage 35.

The reciprocating carriage, indicated in its entirety as at 35, isprovided with a plurality of rollers mounted for rotation on thecarriage about an axis inclined a few degrees with respect to thehorizontal axis of the tubular vmember 18. Preferably the carriage 35comprises two upper sections 36 and 37 and two complementary lowersections 38 and 39. The two upper sections are secured to each other bya bar 4%) at one side of the carriage and a bar 41 at the other side ofthe carriage. Parallel bars 42 and 43 connect the lower carriagesections 38 The upper and lower sections of the carriage 35 areconnected to each other by a vertically extending bolt 44 at one side ofthe carriage and bolt 45 at the other side of the carriage.

A rubber-faced roller 46 is journalled on the bolt 44 and a similarroller 47 is journalled on the bolt 45. i The rollers 46 and 47 fitintothe bottom of the trough or groove formed by the diverging sides ofthe angle irons 15 and 16.

The upper carriage section 36 is provided with a plu-- rality of rollers5d which are journalled to rotate on axes slightly inclined with respectto the axis of the member 13. The section 37 is similarly provided witha plurality of rollers 51 which are similarly mounted with respect tothe member 18. The lower carriage sections 38 and 39 are provided withrollers as at 52 and 53, respectively. These rollers are preferablyfaced with rubber and press against the shaft 18.

When the tubular member 18 is rotated by the driving motor 27 the skewedrollers 50, 51, 52 and 53 frictionally urge the carriage 35 axiallyalong the. member 18. R0- tation of the member 18 in one directioncarries the carriage 35 in one direction along the operator frame androtation of the member 18 in the opposite direction moves the carriageback in an opposite direction along the operator frame.

In FIG. 1 the garage door 8a is connected by links 55 56 to a bracket 57depending from the carriage section 38. The bracket 57 comprises twodepending ears and a pin or bolt 59 extends through the ears topivotally connect the link 56 to the bracket 57. Upon rotation of thetubular member 18 in a predetermined direction by the motor 27, thecarriage 35 is moved to the dotted outline position illustrated inFIG. 1. This moves the top section 8 of the door to the dotted outlineposition which will be referred to here as the open position.

It will be understood by those skilled in the art that the sectionswhich make up the door 8a may be provided with laterally extendingrollers which ride in tracks carried within the garage. The particularsectional construction of the door and the track and the rollers and thecounter-balancing mechanism for the door form no essential part of theinstant invention.

As illustrated in FIGS. "1 and 2, the motor 27 is suspended from theoperator frame. The frame supporting the motor 27 also supports a relaybox indicated at 60. An electric light bulb 61 may, if desired, bemounted at the under side of the relay box, and a portion of amicro-switch 62 projects at the upper side of the relay box. As bestshown in FIGS. 3 and a switch arm 63 is disposed over the projectingportion of the microswitch 62. The micro-switch 62 and the switch arm 63are parts of the control arrangement for the motor 27, as will bedescribed in connection with the electric circuits.

The angle iron 15 carries on the lowermost web thereof a plurality ofapertured brackets 64. The brackets 64 support a rod 65 for rotation.The rod 65 extends along the web of the angle iron 15. A coil spring 66is interposed between the rod 65 and the Web of the angle iron 15 sothat rod 65 and the switch arm 63 fixed thereto is biased to a positionillustrated in FIG. 5 where it is out of contact or slightly above theactuating button of the micro-switch 62. The switch arm 63 may be swungdownwardly against the action of the spring 66 so as to depress thebutton of the micro-switch 62.

The switch arm 63 is secured to rotate with the rod 65 by means of setscrew 67. An actuating assembly 68 is secured to the rod 65 adjacent oneend of the travel of the carriage 35. A similar actuating assembly 69 issecured to the rod 65 adjacent the other end of the carriage travel. Theassembly 68 includes a transverse bar 70 pivoted as at 71. The pivotingmovement of the bar 70 in one direction is limited by the block 72. Thebar 70 is biased to swing into the position shown against the block 72by a coil spring 73 interposed between the bar 78 and the assembly basecarried by the rod 65.

The carriage 35 is provided with a pair of spaced depending cams 74 and75. When the carriage 35 in moving to the left-hand end of the operatorframe brings the cam 74 into engagement with the bar 70 of the actuator68, the stop 72 prevents pivoting of the bar 70 on its pivot 71.Accordingly the edge of the bar 70 in contact with the sloping face ofthe cam 74 is rocked downwardly by the cam and thus the shaft 65 isrocked and the switch bar 63 depresses the micro-switch 62. Thismovement interrupts the power circuit to the motor 27, as explainedhereinafter.

The bar rocking assembly 68 is preferably adjustably secured to the rod65 so that power to the motor 27 is interrupted as the garage doorapproaches its fully open position. The motor 27 and the shaft 18continue to rotate from momentum after the power is interrupted so thatthe cam 74 moves completely past the bar 70, and the carriage 35 and thedoor coast to fully opened position, instead of being driven by poweragainst a limiting stop. This greatly reduces wear and shock on theoperator mechanism and the door itself.

Assuming that the cam 74 has interrupted the motor drive and has passedbeyond the bar 70 as above described, when the operator is actuated soas to move the carriage 35 in the opposite direction, the motion of thecarriage brings the straight side 74a of the cam 74 into engagement withthe bar 70. The carriage overcomes the bias of the spring 73 and the barmerely pivots away from its stop 72 and the carriage 35 moves to theother end of its travel. Thus on the return of the carriage, cam 74 doesnot move the lever arm 63.

The actuator assembly 69 is constructed substantially as the actuatorassembly 68. It includes a pivoted bar 76 which is spring-biased aboutits pivot against a block 77. When the carriage 35 is moved to theright-hand end of the operator frame (as viewed in FIG..3), the cam 75,by means of the bar 76, rocks the rod 65 and again depresses the arm 63and the micro-switch 62 to interrupt the power to the motor. Theassembly 69 is adjustably positioned so as to cut off the power andallow the door and the carriage to coast to fully closed position,carrying the cam 75 completely past the bar 76.

The drive shaft 18 is preferably provided with a pair of oppositelydisposed cam lugs 80 and 81 adjacent the arm 63 and also adjacent themicro-switch 62. Preferably the lugs 80 and 81 are mounted for axialadjustment by reason of the slots 82 and 83, respectively. Fasteningmeans such as cap screws 84 are threaded into the member 18 and may bedrawn up after the proper axial adjustment is made of the lugs 80 and81.

The springs 23 and 24 carried by the stub shafts 19 and 20,respectively, permit limited axial movement of the tubular driving shaft18,.and such movement changes the path of rotation of the cam lugs 80and 81. During the normal operation of the door no loads are imposed onthe tubular driving shaft 18 such as would produce substantial axialmovement of the driving shaft 18. When, however, the movement of thedoor is retarded as, for example, it strikes an automobile or otherobject on its way down, or is caught on its way up, then the force ofthe drive imparted to the tubular driving shaft 18 produces axialmovement of the driving shaft 18. As will be best seen in FIG. 5, axialmovement of the driving shaft in either direction causes either the lug80 or 81 to strike against the bar 63 during rotation of the shaft 18and bring about a depression of the micro-switch 62. By circuit controlmeans hereinafter described in detail, the first depression of themicro-switch by the cams 80 or 81 sufficiently far to close a circuittherethrough interrupts the flow of current to the driving motor, andalso breaks the circuit to the micro-switch so that further movementsthat may be imparted to the micro-switch by the cams as the shaft 18continues to rotate during deceleration of the motor are ineffective. Inthe event the microswitch 62 fails to operate or sticks, the continuedrotation of the shaft causes the cam to cycle the switch until it isoperated properly. This insures reliable operation, eliminating firehazards and the like.

The cams 80 and 81 preferably have rounded exterior surfaces on theirbody portions and tapering rounded points 85 and 86, respectively. Thepoints 85 and 86 taper up to a radial height sufficient to cam themicroswitch 62 closed upon axial displacement of the shaft 18 less thanthe axial length of the points 85 and 86. The radial height of the bodyportions of the cams 80 and 81 is sufiicient to insure depressing themicro-switch far enough to close it firmly but insufficient to damage orbreak the switch if the shaft should rotate several times after shiftingaxially through a greater length than the length of the points 85 and86. The axial length of the cams 80 and 8 1 exceeds the maximum possibleaxial movement of the shaft 18 permitted by the stub shafts 20 and 21and the frame members 7 and 14.

Referring particularly to FIG. 6, I have illustrated diagrammaticallythe electrical control forming a part of my invention. Lines 90 and 91indicate the conventional single-phase A.C. power supply line, usuallyll5 volts. The motor 27 may be any conventional singlephase inductionmotor provided with a starting winding such as a split-phase orcapacitor motor. Such motors can be started in either directiondepending upon the relative connections from the supply line to therunning winding and the starting winding. One problem in connection withsingle-phase reversing motors, however, is

more manual push buttons.

that a certain time must be allowed to elapse between cutting off thepower when the motor is running in one direction and attempting to startthe motor in the opposite direction. If insufficient time is allowed themotor, instead of starting in the reverse direction, will again start orcontinue to run in the same direction in which it was previously run.

The control means and circuit of the present invention eliminate anydanger to the door operator mechanism or to the motor from thischaracteristic. Generally speaking, the control means and circuit arearranged to provide for starting, stopping and reversing of the motor atthe will of the operator by a radio-operated switch or one or Automaticcontrols are arranged to interrupt the power to the motor when the doorhas travelled to a predetermined point in either direction and also tointerrupt the power to the motor when the door is subjected to excessiveresistance to motion in either direction. The automatic controls alsooverride the manual controls and cut off the power to the motor in theevent a manual control should be operated in an effort to reverse themotor but should be operated too soon-after interruption of drive in onedirection. In this event the motor instead of reversing would attempt tocontinue to operate in the same direction even though the connectionshould be reversed by the switch. If this occurs when the door has beenstopped by an obstacle or by reaching the limit of its travel in onedirection the cam 80 or 81 again cuts off the motor power as soon as theshaft 18 has made a revolution.

A low voltage control circuit is preferably provided for the manual pushbuttons for safety reasons. A transformer 96 is connected by means oflines 94 and 95 to the power line 90-91. The transformer output may beabout 24 volts and is effective in the circuit including lines 97 and98. One or more push button switches such as the lines 97 and 98 toclose the normally open relay switch 100. When the push button 99 isreleased or the radio switch 93 opened by termination of the radiosignal the relay 100 again opens. When the relay 100 is closed itestablishes a circuit through the lines 101 and 102 from the powersupply line 90 through the alternating current solenoid 104 of a ratchetor stepper relay and the line 105 to the power line 91.

As known in the art the ratchet or stepper relay includes a pawl '6adapted to engage the teeth of a ratchet disc 107. As diagrammaticallyillustrated the pawl 106 is normally lowered and is lifted one tooth orstep each time the solenoid 104 is energized. The disc 107 is secured toa shaft to which is also secured a cam disc 108 so that the cam disc 108is turned one step each time the solenoid 104 is energized.

As illustrated diagrammatically in FIG. 6 the cam plate 108 is dividedinto steps having three different liftheights, each alternate step 109being of intermediate height and separating a high lift step 110 and alow lift step 111.

The dash-dot outline 112 in FIG. 6 represents a frame which isspring-pressed upwardly and connected to a suitable cam follower 113,the frame 112 being arranged to raise and lower switch contact members115, 116, 117 and 118, each of which is movable between upper and lowercontact points. When the follower 113 is in engagement with anintermediate step 109' of the cam plate 108 the switch members 115 and118 are in their central or off positions as illustrated in FIG. 6. Whenthe cam follower 113 is in engagementwith a high lift step 110 each ofthe four switch elements 115 to 118 is lowered into engagement with itslower contact point and when the follower engages a lower lift step 111each of the four switch ele- 6. ments is raised into engagement with itsupper contac point.

The switch elements 115 and 116 are connected to the power supply line91 by connecting lines 120 and 122, respectively. The switch elements117 and 118 are connected to the power supply line 90 by connectinglines 123 118. The contacts 135 and 136 are cross-connected with thecontacts 133 and 134 by connectors 137 and 138. Thus, when the switchelements 115 and 118 are in their upper position the power line 91 isconnected through the switch element 115, contact 133 and line 131 withthe terminal 127, and the power line 90 is connected through the switchelement 118, contact 135, cross-connector 137 and line 132 with theterminal 123. When the switch elements 115 and 118 are in their lowerposition these connections are reversed; that is, power line 91 isconnected to terminal 123 and power line 90 is connected to terminal127.

The other winding of the motor 27, which in the assumed example is therunning winding, has its opposite ends connected to the terminals 129and 130'. Terminal 129 is constantly connected by line 136 to power line91. Terminal 130 is connected by a line 13-8 to each of two switchcontacts 159 and 140 constituting-the upper and lower switch contactsadapted to be engaged by the switch member 117. Thus, when the switchmember 117 is in either its upper or lower position the power line 90 isconnected through line 123, switch member 117, switch contact 139 or 140and line 138 with the motor terminal 130.

With this arrangement moving the switch contacts from upper to lowerposition reverses the relative connections of the two windings of themotor 27 and in the intermediate position of the switch contacts, asillustratedin FIG. 6, both motor circuits are interrupted.

In order to provide illumination when the door is being opened or closedand for a period of time after the motor power has been cut off, theswitch element 116 is provided with upper and lower contacts 143 and 144which are connected together by a line 145. The line leads to one sideof a heating coil 146 of a thermal delay switch, the other side of thecoil 146 being connected by a line 147 to the power line 90. The thermaldelay switch includes a member such as a bi-rnetal stripdiagrammatically indicated at 148 which is connected to a line 141leading to a lighting device such as the electric lamp 61. The otherside of the lamp '61 is connected to the power line by a line 155.

The bi-metal element 148 is arranged when hot to bend into contact witha switch contact 149 which is connected to a line 142 leading to thepower line 91. When cold the bi-rnetal element 148 moves away from thecontact 149 breaking the circuit. The line is also connected by a line156 to the line 141 leading to the lamp 61.

When the cam 108 moves the switch elements 115 to 118 into either theirupper or lower positions, energizing the motor for operation in onedirection or the other, the switch element 116 makes a circuit throughthe heating coil 146 by means of contact 143 or 144, and at the sametime energizes the lamp 61 through the parallel circuit formed by theline and 156. The heating coil 146 and the bi-metal element 148 arearranged so that the bi-metal element is heated and bent into engagementwith the contact 149 in a shorter period of time than that normallyrequired to operate the door from one of its opened or closed positionsto the other. Thus, another circuit through the lamp 61 is establishedfrom the power line through the line 142, contact 149, bi-metal element148 and lines 141 and 155 before the circuit through the lampestablished by the switch element 116 is broken by the next movement ofthe control relay to off position. Thus, when the switch elements 115 to118 move to their oif positions current continues to flow through thelamp until the heating coil 146 and the bi-metal element 148 have cooledoff sufficiently to permit the bi-metal element to bend away from thecontact 149 and break the circuit. It will be understood, of course,that any desired form of time delay switch may be used and the timingmay be adjusted to maintain the lamp energized for as long a period asdesired after each operation of the motor. One or more manual switches,such as 156a, may be arranged to energize the lamp 61 independently ofthe relay and the thermal switch 146.

The normally opened microswitch 62 is connected in parallel with therelay switch 109 for energizing the solenoid 104 of the stepper relay,but is supplied with current only when the motor is being operated inone direction or the other. For this purpose the switch contacts 139 and140, which are connected together, are also connected by a line 150 witha contact 151 of the micro-switch. The other contact 152 of themicro-switch is connected by a line 153 to the line 102 at connection103.

In FIG. 6 a portion of the shaft 18 and switch arm 63 are illustrateddiagrammatically in inverted position to indicate their relation withthe micro-switch 62. When the switch 62 is depressed by the arm 63,either as a result of the cam 74 or 75 rocking the shaft 65, or as aresult of axial displacement of the shaft 18 and engagement of the cam80 or 81 with the arm 63, the switch element 62 engages and establishesa circuit between the contacts 151 and 152. If the switch elements 115to 118 are in either their upper or lower positions so that the motor isenergized for operation in one direction or the other, closing of thecircuit through the contacts 151 and 152 by the micro-switch 62 suppliescurrent from the power line 90 through the switch element 117 and thelines 150 and 153 to one side of the solenoid 104 of the stepper relay,the other side of the solenoid being connected to the power line 91 bythe line 105. When this occurs the pawl 106 moves the ratchet 107through one step and thereby turns the cam plate 108 one step so thatthe switch elements 115 to 118 are moved to their central positionsopening all of the circuits except the lighting circuit which has beenestablished through the bi-metal element 148. Subsequent operations ofthe micro-switch 62, which may occur as the motor and the operatormechanism decelerate, have no effect since the circuit to themicro-switch has been opened by the switch element 117.

If the door has been moved to either its opened or closed position andthe motor circuit has been interrupted and a person should press thepush button 99' or operate the radio switch 93 before the motor has hadtime to completely decelerate, the solenoid 104 would be energized andwould move the cam 108 to its next step, closing the switches in a wayintended to start the operation of the motor in the opposite direction.When this occurs, however, the motor continues to operate in the samedirection in which it has been turning. Since the door has reached thelimit of its movement in that direction the shaft 18 shifts axially tocause one of the cams or 81 to again interrupt the circuit through themicroswitch 62 and quickly bring the motor to a stop. The skewedrubber-faced rollers 51, 52 and 53 are arranged to provide a substantialdriving force on the carriage but are free to skid on the shaft 18without breaking any of the parts or damaging the motor in the event theshaft rotates further after the maximum permitted axial movement of theshaft. Thus, if the push button or radio switch should be improperlyactuated in an effort to drive the door farther in one direction afterit has reached the limit of its motion or encountered an obstacleneither the mechanism of the door operator nor the motor are subjectedto excessive shock or heating. By adjusting the frictional engagement ofthe skewed rollers with the shaft so that they are incapable of stallingthe motor, even though neither the carriage nor the shaft 18 can moveaxially, the present invention insures that the shaft 18 willnevertheless rotate far enough to actuate the micro-switch 62 by one ofthe cams 80 or 81 thereby interrupting the motor drive.

While .a preferred embodiment of the invention has been described inconsiderable detail it will be understood that various rearrangementsand modifications may be resorted to without departing from the scope ofthe invention as defined in the following claims.

What is claimed is:

1. Door operator means comprising a rotatable shaft mounted for rotationand limited axial movement from a normal position, a carriage engagingsaid shaft and adapted to be reciprocated therealong by rotation of saidshaft, a motor for rotating said shaft, a control circuit for said motorincluding a switch mounted adjacent said shaft, said shaft having a pairof axially spaced cam members projecting from the surface thereof theperipheral extent of said cam being less than 360, said switch beingmounted in a position axially between said cam members in the normalaxial position of said shaft and, said switch being engaged and operatedbetween opened and closed positions by one of said cam members duringeach rotation of ,said shaft when said shaft is shifted axially ineither direction from its normal axial position.

2. A door operator means comprising a rotatable shaft mounted forrotation and limited axial movement from a normal position, a carriageengaging such shaft and adapted to be reciprocated therealong byrotation of such shaft, a motor for rotating such shaft, a controlcircuit for said motor including switching means mounted adjacent suchshaft, said shaft having a pair of axially spaced elongated cam membersprojecting from only one side thereof, said switching means beingmounted in a position axially between said cam members in the normalaxial position of said shaft, said switching means being engaged andoperated between opened and closed positions by one of said cam memberseach time said shaft rotates through one revolution when said shaft isshifted axially in either direction from its normal axial position.

References Cited in the file of this patent UNITED STATES PATENTS292,687 Scott Jan. 29, 1884 2,215,678 Weathers Sept. 24, 1940 2,882,045Moore Apr. 14, 1959 2,887,311 Klamp May 19, 1959

